The present invention is directed to a centrifuge tube holder and, more particularly, is directed to a centrifuge tube holder which provides not only vertical support for the tubes when placed on a workbench, but also horizontal support for the tubes when placed in centrifuge rotor in such a manner that each of at least two tubes have different radial angles with respect the spin axis of the rotor.
In many cases the racks utilized for holding centrifuge tubes while placed on a table top or workbench have a different configuration than the frame utilized for supporting the centrifuge tubes within the rotor during centrifugation. These different configurations necessitate the physical removal of the tube from the tube rack to the support mechanism in the rotor. The movement of the centrifuge tubes especially after the centrifugation run has been completed is undesirable, because it is preferable to impart the least motion or disturbance to the centrifugated sample as possible. Otherwise, the disturbance to the centrifugated sample may be such that the sample may become remixed, rendering it unusable for the purpose intended.
Some prior art arrangements utilize a tube rack which is capable of placement directly in a centrifuge. However, in such case significant modification is necessary for the rotor structure to accommodate the tube rack. Therefore, the rotor must be specifically adapted to handle the particular tube rack construction.
Also, with the previously used types of centrifuge tube racks or holders that are placed in rotors, a separate rack is required for each row of centrifuge tubes to provide the necessary radial or angular orientation with respect to the spin axis in the case of a fixed horizontal tube motor. This results in a limitation in most instances of the number of centrifuge tubes that can be placed in the rotor in the horizontal orientation. Also, the apparatus within the rotor bowl for holding the centrifuge tubes is such that each time the centrifuge tubes are placed as a group in the various locations within the rotor, the rotor must be balanced prior to the centrifugation run. The apparatus within the bowl to support the tubes is typically quite complicated and in some instances is secured in a somewhat permanent basis within the rotor bowl. This causes a disadvantage in attempting to clean the interior of the bowl after centrifugation runs when a sample may possibly leak or spill from the tubes. The irregular shapes of the apparatus used to hold the tubes makes the cleaning of the interior of the bowl inefficient and time consuming.
One distinct disadvantage of most prior art centrifuge tube holders or racks is the tight fit into which the centrifuge tube is placed in the aperture or receptacle portion of the holder. This is required in order to hold the centrifuge tube securely within the rack or holder and prevent the loss of the tube from the rack if the tube holder or the rack is inverted. Therefore, because of this tight fit, the tube is difficult to insert and remove and may cause a jarring or disturbance to the centrifugated sample when trying to remove the tube containing the sample.
Quite often prior centrifuge tube racks or holders are somewhat complicated in design, requiring an expensive overall structure which is neither convenient to use nor economical to manufacture.